The center of a circle is located at (−2, 7) . The radius of the circle is 2. What is the equation of the circle in general form?

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Answer 1 · 2017-05-11T14:45:28

D

D.
It is explained already by another contributor

Answer 2 · 2017-05-11T14:52:29

The answer is the last one, #x^2+y^2+4x-14y+49=0#

We need

#(a+b)^2=a^2+2ab+b^2#

#(a-b)^2=a^2-2ab+b^2#

The equation of a circle, center #(h,k)# and radius #=r# is

#(x-h)^2+(y-h)^2=r^2#

Here, the center is #(-2,7)# and the radius is #=2#

The equation of the circle is

#(x+2)^2+(y-7)^2=4#

#x^2+4x+4+y^2-14y+49-4=0#

#x^2+y^2+4x-14y+49=0#